1. Field of the Invention
The present invention relates to a recording apparatus capable of recording while maintaining a suitable gap between a recording head and a recording surface of recording media with various thicknesses.
2. Description of the Related Art
A recording apparatus having functions of a printer, a copying machine, a facsimile machine, etc., or a recording apparatus used for an output terminal of a complex-type electronic apparatus or a workstation having computers and word processors therein is constructed so as to record an image on a recording member (recording medium) such as a paper sheet or a plastic sheet on the basis of image information. Such a recording apparatus may be classified into types of inkjet, wire-dot-matrix, matrix, thermal, laser beam, and so forth.
On the other hand, demands for a material of the recording member are diversified, so that it has been required to form images on a thin paper sheet and a converted paper sheet (such as a paper sheet for filing with punched holes, a paper sheet perforated for tearing-off, and a paper sheet with an arbitrary size) as well as on an ordinary recording member such as a paper sheet and a resin sheet (OHP, etc.).
In the recording apparatuses described above, however, there are some apparatuses that cannot have images with desired recording quality without maintaining a suitable gap between a recording surface of a recording material and recording means. For example, in an ink-jet recording apparatus, in order to obtain clear images with high quality, it is ideal that the gap between an ink-ejection face of a recording head and a recording surface of a recording material be as small as possible and be equal as possible over the entire recording surface of the recording material.
In view of roughness of a recording surface of a recording material, however, in order to avoid ink stain of recorded images and recording head wear due to the friction between the recording head and the recording material, an appropriate gap between the recording head and the recording surface of the recording material has to be maintained.
For that purpose, in inkjet recording apparatuses for ink-jet recording on recording materials with various thicknesses such as plain paper and postcards, in order to maintain a predetermined gap between the recording head and the recording surface of the recording material, there are provided a system in which the recording head is displaced in any one of directions approaching and separating from the recording material and a system in which the recording material is displaced in any one of directions approaching and separating from the recording head. In any one of the systems adopted, the gap (referred to as the xe2x80x9chead gapxe2x80x9d below) between an ink-ejection face of a recording head and a base position, which is the back surface of the recording material opposite to the recording surface adopted as a base point (or a position for supporting the recording material of a platen adopted as a base point), is adjusted so as to correspond to recording material with various thicknesses. For example, in an ink-jet recording apparatus in which the back surface of the recording material is supported by the platen, the gap between the platen and the recording head (that is, the gap between the recording head and the platen position for supporting the back surface of the recording material, which is to be the head gap) is adjusted so as to correspond to the thickness of the recording material.
As positions for setting the head gap, there are generally two positions of a xe2x80x9cthin-paper positionxe2x80x9d for setting the head gap smaller according to plain paper and high-quality media and of a xe2x80x9cthick-paper positionxe2x80x9d for setting the head gap larger according to recording material having thicknesses larger than those of the plain paper such as envelopes and postcards.
When forming images on a plain paper sheet by ejecting ink drops with high density, the surface of a recording material is liable to deform so as to curl to have roughness thereon due to paper swelling, so that the recording material and the recording head may rub against each other. In such a case, even when the recording material is plain paper equivalent to thin paper, the head gap position for thick paper (thick-paper position) may be set and a user may freely switch the head gap position according to situations.
In the conventional example described above, however, although a user can freely switch the head gap position, even when better images could be obtained by using a smaller head gap, the user may leave the head gap at the thick-paper position, so that images with inferior quality may be consequently output.
In particular, when forming images by ejecting ink at both forward and reverse scans during reciprocation of a carriage, when a position other than the optimum position is selected, the positions of ink drops depositing on the recording material in the forward scan may deviate from those in the reverse scan, so that excellent images may not be obtained.
When the larger head gap is preferable in such cases as for envelopes and postcards, if a user performs recording by leaving the head gap at the thin-paper position, the recording head may come into contact with the recording material, which may result in having recorded images stained with ink.
In order to prevent such problems in advance, a system for detecting a recording-operation state such as a head gap state has been demanded, and a simplified detecting system using the structure of a conventional recording apparatus as much as possible is especially required as such a system.
In view of the problems described above, the present invention has been made, and it is an object of the present invention to provide a recording apparatus, in which a position of a movable end of a carriage moving serially corresponds to a recording-operation state of the recording apparatus.
It is another object of the present invention to provide an ink-jet recording apparatus, in which a gap between a recording head and the back surface of a recording medium or a platen part for supporting the recording medium corresponds to a position of a carriage for moving a recording head mounted thereon serially.
It is another object of the present invention to provide an ink-jet recording apparatus which detects or recognizes the existence of a gap between a recording head and the back surface of a recording medium or a platen part for supporting the recording medium, and the apparatus can record the optimum images according to the gap which is a head-gap distance.
It is another object of the present invention to provide an ink-jet recording apparatus or an ink-jet recording method, a carriage for serially moving a recording head, position detecting means for detecting the position of the carriage in the serial direction, and changing means for adjusting the distance between the recording head and a recording medium, and wherein the apparatus performs image recording according to the distance by detecting a state of the changing means on the basis of information from the position detecting means.
It is another object of the present invention to provide a recording apparatus, a carriage for serially moving a recording head, changing means for changing the movement of the carriage according to a recording state of the recording apparatus, position detecting means for detecting a position of the carriage in the serial direction, and recognizing means for recognizing a recording state of the recording apparatus by detecting a serially movable range of the carriage from the position of the carriage detected by the position detecting means.
Further objects, features and advantages of the present invention will become apparent from the following description of the preferred embodiments with reference to the attached drawings.